The shelf-life of the yerba-mate chimarrão depends on the industrial processing and packing type. The alteration that the yerba-mate suffers during the stockpiling is the microbial growth in function of the humidity absorption. The present work had as objective the counting microbiology and the humidity determination and activity of water, during a period of 180 days. The results obtained for the determinations microbiology were below you limit maximum established by effective legislation. The medium value of humidity was of 3.63%; activity of water was 0.306. In that work the important function of the packing was evidenced in the conservation of dehydrated foods.